1. Field of the Invention
The present invention relates to a positioning method for attaching a solder ball to an electrical connector and the connector using the same, particularly to a positioning method for obtaining coplanarity of a matrix of solder balls soldered on a bottom face of an electrical connector.
2. The Prior Art
Ball grid array is popular in manufacturing of CPU packages and printed circuit board and it also becomes a trend in manufacturing of an electrical connector. Referring to FIG. 4, normally a soldering tail 31 is formed at a lower end of each contact of an electrical connector 1 for engagement with a solder ball 3 via soldering. A mesh (not shown), similar to that used in a screen painting procedure, is used to align the solder balls 3 to corresponding soldering tails 31 of contacts before soldering to a printed circuit board (not shown). However, a solder ball 3 is apt to engage with the soldering tail 31 at an edge thereof during soldering due to its rolling feature. However, any of the solder balls 3 if soldered on the edge of the soldering tail 31 will critically damage the coplanarity of the solder balls thus adversely affecting the soldering of the connector 1 to the printed circuit board. It is requisite to provide a new method by which the solder balls can be soldered onto the right positions thereby guaranteeing the coplanarity of the solder balls when they are soldered on the soldering tails.